Producing ammonium sulfate.



. man Empire,

ALWIN MITTASCH. AND

HUGO MORAWITZ, or MANY, nssxouons TO Bamso ir: ANILIN THERHINE, GERMANY,A. CORPORATION.

LUDWIGSHAFEN-ON-THE-RHINE, GER- & SODA FABRIK, OF LUDWIGSHAFEN-ONIRODUCING AMMONTUM SULFATE.

- 1,991,234. Specification of Letters Patent.

No Drawing.

To all whom it may concern Bc it known that we, ALWIN MITTASCH and HUGOMORAWITZ, citizens of the Gerthe-Rhine, Germany, have invented new anduseful Improvements in Producing Aminonium Sulfate, of which thefollowing is a specification.

The oxidation of ammonium sulfite in solution by means of oxygenor airproceeds generally so slowly that it has hitherto been preferred toobtain the salt in the solid state and then oxidize it in order toconvert it into ammonium sulfate. We have now found that the oxir'atiionof ammonium sulfite in the form of solution can be carried out easilyand rapidly by treating the solution with oxygen, for instance with pureoxygen, =or air, in the presence of a body whichtis capable of acting asan oxygen carrier, while maintaining the solution alkaline with ammonia.As examples of suitable oxygen carr ers we men- 'tion porous substancessuch as carbon, theclay, pumice stone, ferric oxi'd and man ganesedioxid, mixtures can, also be employed, for instance the oxygen carriermay contain platinum, manganese compounds, iron compounds, or ceriumcompounds, and it is possible according to our invention to employ inthe solid state oxygen carriers or catalysts which are soluble in acid.

The oxidation herein referred to is preferably carried out at a raisedtemperature and, if desired, the production of the solution and itsoxidation can be carried out in the same apparatus. The ammonium sulfitesolution can also contain some solid arnmonium sulfite, which latterduring the OXldation gradually goes into solution and then becomesoxidized. A, simple method of maintaining the solution alkaline is toadd ammonia repeatedly or continually. The

process according to our invention readilypermits of the production ofsaturated or even of supersaturated solutions of ammonium sulfate, fromwhich the solid sulfate then separates out in a pure state.

It is often advanta cons to carry Jutthe process of our inven ion underincreased,

- pressure, since the reaction then proceeds even more rapidly andcomplete oxidation can be obtained n a very short time when residing atLudwigshafen-on- 20 atmospheres,

.a little ammonia 7 place the small quantities of ammonia which PatentedMar. 24 1914,

Application filed October 20, 1918. Serial No, 796,120.

using either oxygen or even air as the oxi 12mg agent. p The followingtrate further. the nature of our invention, but the invention is notconfined to this example. v I

Place concentrated ammonium sulfite solution containing a small excessof ammonia in an autoclave containing pieces of porous clay coated withmanganese 'hydroxid and then, while maintaining'a temperature of orabout 80 C. and a pressure of or about 'pass a current of air throughthe solution. It is preferred to add to the airin order to repass awaywith the gases from the auto clave and which can be readily recovered inany suitable manner. If desired, two or more autoclaves can be connectedin series.

Now what we claim is 1. The process of producing ammonium sulfate bytreating ammoniumsulfite in solution with oxygen in the presence of anoxygen carrier while maintaining the solution alkaline with ammonia. v

2. The process of producing ammonium sulfate by treatingammonium'sulfite in solutionwith oxygen in the presence of'an oxygencarrier While maintaining the solution alkaline with ammonia and Whilecarrying out the reaction under increased pressure.

3. The process of producing ammonium sulfate by reacting on ammoniumsulfite with oxygen in the presence of porous clay covered withmanganese hydroxid and of an excess of ammonia. v LThe process ofproducing ammonium sulfate by reacting on ammonium sulfite with oxygenin the presence of porous clay covered with manganese hydroxid and of anexcess of ammonia, while carrying out the reaction at a pressure ofabout twenty atmospheres.

In, testimony' 'whereof We have hereunto set our hands in the presenceoft'vvo subscribing witnesses- 'ALWIN MITTASCH. 1 TIUGO MORAWITZ.Witnesses: i

r CHRISTIAN Sormnmnn,

ALEo, LLOYD.

example will serve to illus

